860 



REPORT or COMMISSIONER OF FISH AND FISHERIES. 



[4] 



spawn after a summer's fast. To arrive at a correct estimate of their 

 rate of growth, we should compare their size when retaken with their 

 probable size at the time of their original capture in June, 1880. The 

 record books show the weight of spawn taken from each female. The 

 difference between the average of estimates in June and of ascertained 

 weights in November may be taken to represent the waste of flesh dur- 

 ing the period of confinement. This is found to be 10.5 per cent, of the 

 November weights before spawning. Calculating the original weight 

 from these data the following table may be constructed, to exhibit the 

 rate of growth : 



Thus the four females made in two years an average increase of 31.9 

 per cent, in weight, and of 14.2 per cent, in length. Those varying 

 from 10 to 12 pounds on original appearance range from 16.50 to 21 

 pounds on recapture. 



Taken in connection with previous experience at this station, the re- 

 sults obtained from this experiment warrant us in saying that salmon 

 visit the Penobscot Eiver for the purpose of spawning but once in two 

 years, and that they visit it for no other purpose is well established. 



